Adjusting the hydraulic braking effect of the hydraulic partial braking system, in this context, should take place, in the optimal case, unnoticed by the driver, particularly without a reaction for the driver, based on a changing feel of the brake pedal, an offset of the brake pedal or a change in the force to be exerted in its operation. For this reason, in such overall braking systems there is frequently provided a complete decoupling of the operating unit, that is, the brake pedal, for example, from the hydraulic braking system; the driver operates only a pedal simulator, in this context. A force transmission from the driver to the wheel brakes is frequently not provided in such systems, or is interrupted by closing a valve, for example, which connects the main brake cylinder hydraulically to a wheel brake. This may, however, influence the safety of the braking system, particularly in the case of the failure of a brake force-generating arrangement.
German document DE 10 2009 007 494 A1 discusses a braking system, in which, as mentioned above, the driver is separated in the case of a generatorical braking of the brake circuit.